Not Applicable.
Not Applicable.
Not Applicable.
1. Field of the Invention
This invention relates to the field of telescopic sights for firearms. More specifically, the invention comprises a detachable mount for a telescopic sight that can be detached using one hand without adjusting the customary grip on the firearm.
2. Description of the Related Art
Detachable mounts for telescopic sights have been in use for approximately one century, owing to a long-recognized need. Firearms, particularly sporting rifles, are relatively durable items capable of withstanding wide variations in atmospheric conditions and substantial physical shock. Telescopic sights, in contrast, are relatively delicate optical instruments. Although their design has been advanced considerably in recent decades, telescopic sights remain vulnerable to variations in atmospheric conditions and to physical shock. A sharp blow to a telescopic sight will often shift its point of aim. Worse, there is no visual indicator of this shift, meaning that the user is often unaware of the shift until a shot is fired and missed.
As a result of these factors, hunting rifles with permanently attached telescopic sights must be treated delicately. It has therefore long been recognized that the ability to detach the telescopic sight until it is needed is highly desirable. One such type of detachable mount is disclosed in U.S. Pat. No. 5,035,487 to Herz (1991). While effective, the Herz type of device is slow to operate. The user must hold the rifle securely while using his or her free hand to rotate the small levers employed to engage the scope mounts. These levers do not provide much mechanical advantage. Both must be rotated independently to the correct position. The telescopic sight must then be lifted off without tiltingxe2x80x94or the device tends to become stuck.
In hunting situations, the telescopic sight must often be removed rapidly. This is particularly true when following up wounded game. In such close range work, the use of the open (sometimes called xe2x80x9cironxe2x80x9d) sights on the rifle is generally preferred. Thus, a scope which could be removed quickly using a single latching device is preferable.
The Herz device also incorporates the interaction of camming surfaces generating high surface friction. There is no accommodation for wear compensation. Thus, as the device is used over time, the interlocking surfaces tend to wear loosexe2x80x94eventually rendering the device inoperable.
One type of detachable mount using a single latching device is known as the xe2x80x9cEuropean claw.xe2x80x9d This type of mount dates back to approximately World War I. Printed sources within the art sometimes refer to this type of mount as a xe2x80x9cSuhlerxe2x80x9d mount. Though the Applicant is unable to verify the origins of this name, one would assume that xe2x80x9cSuhlerxe2x80x9d refers to the individual who originally created the design.
The Suhler mount is relevant to the consideration of the present invention. As the Applicant is unable to discover a prior patent disclosing the details of the Suhler design, the Applicant is submitting the details herewith. FIG. 1 illustrates the prior art Suhler mount. Rifle receiver 10 is of the common bolt-action type. Barrel 12 is threaded into rifle receiver 10. Rifle receiver 10 has a forward cylindrical portion referred to as receiver ring 22, and a rear portion referred to as receiver bridge 24. The particular receiver illustrated is of the Mauser type, which is the rifle type most closely associated with the Suhler mount.
In preparation to installing the Suhler mounts, dovetail cut 44 is milled into receiver ring 22. Front Suhler base 46 is then press-fit laterally into front dovetail cut 44. In some instances, it may also be soldered in place. The reader will observe that the upper planar surface of front Suhler base 46 opens into two front Suhler slots 50.
Rear Suhler base 48 is installed on receiver bridge 24 in one of two ways. Some receiver bridges have an upstanding lug into which a lateral dovetail cut can be made. If this is the case, then rear Suhler base 48 is press fit into place (and possibly soldered) in the same fashion as for front Suhler base 46. Other receiver bridges have only a rounded cylindrical surface that is too thin to accommodate a dovetail cut. In that case, rear Suhler base 48 is soldered onto the top of the receiver bridge in an operation obviously requiring considerable skill and precision. Rear Suhler base 48 has a pair of rear Suhler slots 52.
At the time the Suhler design was created the object was to mount old scope sight 56. FIG. 2 shows such a telescopic sight. Old scope sight 56 is a type of telescopic sight which is now rarely seen, but was once quite common. The reader will note that it consists primarily of a long featureless cylinder having a relatively small diameter (typically one inch or 30 mm). Only the eyepiece has a larger diameter. Modern scopes have a much larger objective lens (the forward lens) diameter. The significance of this difference will become apparent subsequently.
Still referring to FIG. 2, the reader will note that rear ring 60 and front ring 58 are attached to old scope sight 56. These are typically positioned on old scope sight 56 and soldered in place. Rear ring 60 has two descending rear Suhler lugs 64. The rearward facing surfaces of these two lugs are each cut by Suhler mating notches 68.
Front ring 58 has two descending front Suhler lugs 62. The forward facing surfaces of these two lugs are angled to form mating surfaces 66. FIG. 3 shows rifle receiver 10 with old scope sight 56 in place. The figure incorporates a cutaway through both the front and rear Suhler bases to show the internal features of the nearest set of Suhler slots. The reader will observe that front Suhler lug 62 rests within front Suhler slot 50, and rear Suhler lug 64 fits within rear Suhler slot 52.
Suhler slider 54 is biasedxe2x80x94typically by springsxe2x80x94to move forward (right to left in the view as shown). Returning briefly to FIG. 1, the ends of Suhler slider 54 actually extend out beyond the sides of rear Suhler base 52. A tab is attached to each exposed end to facilitate grasping by the user. These tabs are actually identified as Suhler slider 54 in FIG. 1.
Returning now to FIG. 3, the operation of the devie will be described. When the user releases the tabs, Suhler slider 54 is pushed forward where it engages mating notch 68. This interface prevents any vertical motion of rear ring 60, and also pushes the entire assembly of the scope and rings forward. That forward motion brings mating surfaces 66 on front Suhler lugs 62 in contact with corresponding surfaces on front Suhler slots 50 (the rearward facing surfaces). The reader will observe that these mating surfaces are inclined from the vertical. The result is a wedge interactionxe2x80x94with front ring 58 being pulled firmly down as it is forced forward. When the mating surfaces are fully engaged, any further forward movement is stopped.
The spring bias forcing Suhler slider 54 forward therefore locates the device securely along the axis of the rifle""s barrel. The interaction of Suhler slider 54 and mating notches 68 limits the vertical motion of rear ring 60. The interaction of mating surfaces 66 with corresponding surfaces in front Suhler base 46 limits the vertical motion of front ring 58. The lateral fit between the four descending lugs and the four slots in the Suhler bases limit any lateral motion. Thus, the telescopic sight is locked securely in place.
FIG. 4 illustrates the removal of the device, also using a cutaway through the bases. When the user wishes to remove old scope sight 56, he or she grabs Suhler slider 54 (using the attached tabs) and pulls it rearward. Suhler slider 54 then travels free of mating notches 68 in rear Suhler lugs 64. At this point, the user grasps the rear portion of old scope mount 56 and rotates it upward as shown. Once rear Suhler lugs 64 are clear, the user may pull front Suhler lugs 62 free of front Suhler base 46 as well. He entire assembly is then removed.
Installation of the device is basically the reverse of the process just described. The user starts by placing front Suhler lugs 62 in front Suhler base 46. The user then pulls back on Suhler slider 54 (using the tabs), which allows rear Suhler lugs 64 to drop into rear Suhler base 48. The user then releases the tabs, allowing the device to engage and lock. It should be noted that some rear Suhler lugs 64 incorporate a beveled lower surface which automatically moves Suhler slider 54 rearward when the rear of old scope mount 56 is pressed down firmly (thereby eliminating the need for the user to grasp the tabs to attach the scope). This variation is actually the one illustrated.
FIGS. 3 and 4 also serve to illustrate a significant limitation of the Suhler design. The forward portion of old scope sight 56 is labeled in FIG. 3 as scope bell 18. This term is now in common use because modern scope sights have an objective lens which is much larger in diameter than the central tube. Thus, the forward portion of the scope is bell-shapedxe2x80x94the diameter grows larger toward the forward end. This phenomenon is obviously not seen on old scope sight 56. Nevertheless, for purposes of consistency, the forward portion will be referred to as scope bell 18.
In FIG. 4, the reader will observe that the scope must be tilted forward to remove it from the prior art Suhler mounting system. This results in scope bell 18 very nearly contacting barrel 12 or rear sight 14. There is barely sufficient clearance for old scope sight 56 to be removed. Turning briefly to FIG. 8, the reader may observe modern scope sight 16. Scope bell 18 on modern scope sight 16 is both longer and larger than the one found on old scope sight 56. Returning now to FIGS. 3 and 4, those skilled in the art will readily appreciate that a modern scope sight cannot be used on the prior art device illustrated, since it cannot be removed due to the mechanical interference between scope bell 18 and the rifle.
The Suhler mount suffers from a second inherent drawback. Not only have modern scope sights grown larger, they are also considerably heavier than old scope sight 56. The inertial forces generated under rifle recoil are therefore more significant. The front interface between bases and lugs in the Suhler mount is a pure metal-to-metal contact. The rear interface, in contrast, depends on the spring loading of Suhler lug 54.
Returning now to FIG. 3, when the rifle is fired, rifle receiver 10 undergoes a sharp rearward impulse. This movement is imparted to front ring 58 as recoil impulse 106 (the geometry prohibits any significant transfer through rear ring 60). Because recoil impulse 106 is applied well below and in front of the center of gravity of old scope sight 56, it generates recoil torque 108. Recoil torque 108 tends to force old scope sight 56 to rotate in a counterclockwise direction (in the view as shown). This, in turn, tends to lift rear ring 60 out of rear Suhler base 48. Thus, substantial recoil tends to loosen the device.
Those skilled in the art will also realize that the mechanical interface between Suhler slider 54 and mating notch 68 must be fitted very carefully in order for the device to work. This fitting is typically done by hand, using the Prussian blue or xe2x80x9cthickness of smokexe2x80x9d process of scraping away the high spots to produce a perfect fit. As the device wears over time, this mechanical fit often tends to become loose.
Accordingly, the prior art devices are limited in that they:
1. Require the operation of multiple latching mechanisms to apply or remove;
2. Do not allow the use of modern telescopic sights having large objective lenses and substantial weight;
3. Tend to loosen under recoil;
4. Do not incorporate wear compensating features; and
5. Require hand fitting of the interfacing components.
The present invention comprises a detachable mount for a telescopic sight which can be operated using only one latching mechanism. The mount uses a front base attached to the ring of a rifle receiver and a rear base attached to the bridge of a rifle receiver. The upper surfaces of both the front and rear bases open into a pair of slots. A separate scope mount is attached to a scope sight by conventional means. Two sets of lugs descend from the lower surfaces of this scope mount. These sets of descending lugs are configured to fit securely within the slots in the front and rear bases when the scope mount is placed over the bases.
The forward facing surfaces of the rear set of descending lugs mate with a corresponding set of rearward facing surfaces in the slots within the rear base. These sets of mating surfaces are offset from the vertical to create a wedging effect that pulls the rear of the scope mount down when it is pushed forward relative to the rifle receiver.
The rearward facing surfaces of the front set of descending lugs open into tapered notches. The front base incorporates a transverse slider having a tapered surface which fits within the tapered notches in the front descending lugs. The interaction of this slider with the front lugs pushes the front of the scope mount forward while simultaneously pulling it down. The forward motion also serves to pull the rear of the scope mount down as described previously. Thus, the forward motion of this transverse slider tends to seat the scope mount firmly on the two bases.
When the user wishes to remove the device, the user pulls the transverse slider rearward and lifts the front of the scope mount up until the front lugs clear the front base. The user then pulls the rear lugs free from the rear base, thereby completely detaching the scope. Installation is the reverse of this procedure.
The geometry of the device employs the recoil impulse to actually promote engagementxe2x80x94rather than loosening it. The geometry also incorporates wear-compensating features. Finally, the geometry provides removal clearance for very large scope sights since the front of the scope is lifted for removal, rather than the back.